Resumo
This study evaluated the sensitivity of Malassezia spp. strains, the etiologic agent of pityriasis versicolor, to essential oil from Cymbopogon citratus. The chemical composition of the essential oil was analysed by GC-MS, and the major constituents were: geraniol (52.80%), neral (36.65%) and myrcene (3.73%). The minimum inhibitory concentration (MIC) of C. citratus essential oil on to 22 strains of Malassezia spp. were determined by agar dilution technique in the presence and absence of ergosterol (50-250 ìg/mL) and sorbitol (0.8 M). Increased MIC values in the presence of ergosterol indicate an effect on fungal membrane, and the higher MIC values in the presence of sorbitol indicate a mechanism of action on thecell wall. The MIC ranged from 0.31 to 1.25 ìL/mL and it increased fourfold in the presence of ergosterol, regardless of concentration tested; and this fact was most likely related to the occurrence of the oil and exogenous ergosterol complexes. No change in MIC values in the presence of sorbitol was found. The sedata infer that C. citratus essential oil causes an effect on Malassezia spp. plasma membrane synthesis by binding to ergosterol. This study contributes to the development of new antifungal drugs, especially against Malassezia spp. (AU)